In high voltage applications, dielectric breakdown strength of materials are employed to determine equipment size in design, and therefore power level. For example, to manufacture compact power transformers or cables for energy transmission with high power ratings, one needs to improve either the current carrying capacity of the conductors utilized or the electrical insulation properties of the utilized dielectric that withholds the system voltage. The product of the system current and voltage yields the system power rating.
The current electrical insulation technology uses many polymers (thermoplastics and thermosets). Polymer materials are extensively used in high voltage applications. Recently metal-oxide nanoparticle filled polymers have been shown to have improved electrical insulation properties. In these systems, uniform dispersion of particles is very important for obtaining materials with better electrical insulation and desired physical properties. Conventional mixing methods use ex-situ particles with relatively expensive high shear mixing techniques, such as twin-screw extruder. As such, a need continues for improved methods of homogeneously distributing nanoparticles in a polymer matrix to provide insulating materials.